The Holbrook, Arizona fall of 1912 is a classic event in meteoritics both for its scale and its availability. Holbrook is a common fall in collections and complete individuals range from sub-gram six kilos, and from fresh-after-the-fall to found yesterday.
The L6 chondrite fell not far from the famous Meteor Crater. About 60 miles by road in fact. And even less as the meteorite flies. Another popular meteorite hunting site called Gold Basin is about 280 miles away. So you could fill a weekend vacation with some world-class meteorite experiences and a good chance you might actually find something although that something might be the size of a head of pin. A pin from outer space no less!
There are five carats in one gram. Since these Holbrook peas are often sub gram, and even in the tenth-of-gram range, using carats to describe their weight is completely acceptable.
One of the lucky things about the Holbrook fall was that many specimens were collected very shortly after the fall. Thousands of them. And a disproportionate number (by general collection standards) of those fresh stones were actually painted with a specimen number and recorded into a collection catalog.
The only comparisons I can think of, and both pale to Holbrook in volume of numbered pieces, are Pultusk and Norton County. Pultusk, the Polish H5 that looks quite similar to Holbrook (I wouldn’t be surprised if Holbrook and Pultusk both grew up in the same neighborhood in the Asteroid Belt albeit one in a higher iron home), but while there are many tiny Pultusks, I’ve not heard that anyone spent time actually numbering the individual stones. Norton County was a massive Aubrite fall that produced many fragments, and a shocking number of individual fragments were logged into the collection of the Institute of Meteoritics in New Mexico, mostly due to the work of Lincoln LaPaz.
The main creator of “Numbered Holbrooks,” as they are known, is the American Museum of Natural History in New York City. The second most prolific pea painter was W. M. Foote who collected nearly 220kg of Holbrook specimens and likely the source of most of the freshly-fallen stones we now display.
With all the emphasis on larger specimens, take some time and enjoy the small ones and feast on Peas and Carats.
Until next time….